package com.cycle.community.entity;

import lombok.Data;

/**
 * 封装分页相关的信息
 *
 * @author lenovo
 * @create 2022/8/11 20:43
 */
@Data
//TODO current>=1
//TODO limit>=1&&limit<=100
//TODO rows>=0
public class Page {
    /**
     * 当前页码
     */
    private int current = 1;
    /**
     * 显示上限
     */
    private int limit = 10;
    /**
     * 数据总数(计算总页数)
     */
    private int rows;
    /**
     * 查询路径(复用分页链接)
     */
    private String path;

    /**
     * 获取当前页的起始行
     *
     * @return
     */
    public int getOffset() {
        return (current - 1) * limit;
    }

    /**
     * 获取总页数
     *
     * @return
     */
    public int getTotal() {
        return (rows % limit == 0) ? (rows / limit) : (rows / limit + 1);
    }

    /**
     * 获取起始页码
     *
     * @return
     */
    public int getFrom() {
        int from = current - 2;
        return from < 1 ? 1 : from;
    }

    /**
     * 获取结束页码
     *
     * @return
     */
    public int getTo() {
        int to = current + 2;
        int total = getTotal();
        return to > total ? total : to;
    }

}
